The overall performance of a detergent product for use in washing or cleaning method such as laundry, dishwashing or hard surface cleaning, is judged by a number of factors, including the ability to remove soils and the ability to prevent redeposition of the soils, or the breakdown products of the soils on the articles in the wash.
Removal of stains stemming from plants, wood, mould-clay based soil and fruits is one of today's toughest cleaning task; in particular with the trends to move to low wash temperatures. These stains typically contain complex mixtures of fibrous material based mainly on carbohydrates and their derivatives: fibres and cell wall components. Plant based soils are additionally accompanied with amylose, sugars and their derivatives.
Food soils are often difficult to remove effectively from a soiled substrate. Highly coloured or "dried-on" soils derived from fruit and/or vegetable juices are particularly challenging to remove. Specific examples of such soils would include orange juice, tomato juice, banana, mango or broccoli soils. The substrates can be fabrics, dishware or hard surfaces.
Pectic substances are found in, for example, fruit juices. The pectic substances act to hold dispersed particulates in suspension in such fruit juices, which will tend to be viscous and opaque in nature. Pectic enzymes are commonly used in the fruit/vegetable juice processing industry in the clarification of juices by breakdown of the pectic substances therein (depectinisation).
Benefits for the specific use of pectinesterase enzymes which are substantially free from other pectic enzymes in detergent formulations, particularly for use in laundry, dishwashing and household cleaning operations have not been recognised.
DE 36 35 427 is directed to phosphate-free detergents for cleaning clothes, containing enzymes with pectinase activity, which is said to include such enzymes as polygalacturonase, pectin lyase and/or pectinesterase. However, aside from the general teaching therein related to mixtures of these pectinase enzymes for the removal of inorganic soilings from clothes, the only specific teaching regarding an individual pectinase enzyme is found in example 3, where the enzyme (designated "Enzyme D") is characterised as containing a large quantity of pectin lyase. Table III provides the results of the evaluation of this Enzyme D in a detergent formulation, indicating that this high pectin lyase mixture has the highest % pectinase activity (10%) and one of the higher detergency values (83%) in combination with water-soluble high molecular compound, by comparison to the other enzyme compositions reported.
It is an object of the present invention to provide laundry, dishwashing or household detergent compositions which provide soil/stain removal benefits when used in washing and cleaning operations.
According to the present invention, it has now been surprisingly found that the pectinesterase enzymes substantially free of other pectic enzymes and especially the alkaline pectinesterase enzyme substantially free of other pectic enzymes, provide significant removal of broad range of body, plant and fruit based stains and enhance the realistic item cleaning profile of the detergent compositions.
Indeed, the inclusion of pectinesterase enzyme substantially free of other pectic enzymes and especially the alkaline type, provides in particular improved removal of body soils, dried-on fruit and vegetables juice soils/stains.
In addition, it has been found that the alkaline pectinesterase enzyme substantially free of other pectic enzymes presents improved compatibility and enhanced activity in the wash solution thereby providing improved removal of body, dried-on fruit and vegetables juice soils/stains, especially when stemming from heavy duty laundry or dishwashing compositions. It has also been found that the alkaline pectinesterase enzyme substantially free of other pectic enzymes demonstrates a better compatibility with detergent matrix, e.g. during product process and shelf life.
Furthermore, it has also been surprisingly been found that the inclusion of dispersants, particularly organic polymer dispersants, is of great value in detergent compositions containing pectinesterase enzymes. The dispersants aid dispersion of the breakdown products of the enzymatic soil degradation, thus preventing their redeposition on articles on the wash.
Improved cleaning performance has been also observed when the pectinesterase enzymes are combined with other detergent enzyme. Enzymatic bleaching system or conventional activated bleach system together with pectinesterases provides enhanced performance benefits on a wider range of stains.
Furthermore, polymers providing dye transfer inhibition combined with pectinesterase enzymes results in improved whiteness maintenance and/or soil release properties.